JPH092204A - Gas generator of power generator for seat belt winding - Google Patents

Abstract

(57) [Abstract] [Purpose] A seat belt winding power generation device capable of concentrating a flame in a small-diameter pipe line during operation of a detonator and rapidly supplying heat to the gas generant chamber. It is to provide a gas generator. [Structure] A cylindrical casing having an opening on one side, a cylindrical holder chamber formed on one side in the casing, and a holder chamber which is continuous with the holder chamber via a step formed on the inner wall surface of the casing. A gas generant chamber having a diameter smaller than the inner wall surface of the chamber, an igniting agent and a driving agent contained in the gas generant chamber, and a detonator having a detonator chamber housed in the holder chamber and opening to one side of the casing. The holder, the caulking portion formed on one side of the casing for pressing the detonator holder, the detonator held in the detonator chamber, the gas generator chamber formed in the detonator holder and the detonator chamber, and the end portion on the detonator chamber side. And a small diameter conduit in which an inverted conical taper portion having a taper angle of 60 ° to 120 ° is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seatbelt retracting power generator for supplying power to an emergency retractor of a seatbelt retractor, and more particularly to a gas for supplying gas to this device. The present invention relates to the improvement of the ignitability of the igniting agent of the generator and the driving agent.

[0002]

2. Description of the Related Art Generally, a vehicle such as an automobile is provided with a seat belt for protecting an occupant from a shock at the time of a collision. The seat belt wound around the occupant is restrained by a seat belt retractor.

Then, at the time of recent, sudden stop or collision,
In order to reliably protect the driver with a seat belt, a seat belt retractor that retracts the seat belt,
It is required to arrange an emergency retractor and instantaneously retract the seat belt by this emergency retractor. As such a seat belt retractor, for example, an actual flat belt 1-2403
The one shown in Japanese Patent Publication No. 45 is known.

This will be described with reference to FIG. In the figure, after the seat belt 104 wound up from the seat belt retractor 103 fixed to the lower part of the center pillar 102 of the vehicle body 101 passes through the through ring 105 mounted above the center pillar 102. The seat belt end portion 107 is attached to the rear side surface of the seat 106, which extends downward.

A tongue plate 108 is provided between the through ring 105 of the seat belt 104 and the seat belt end portion 107 so as to be movable along the seat belt 104. The occupant seated on the seat 106 moves from the seat belt retractor 103 to the seat belt 10
After pulling out the seat belt 104, the tongue plate 108 is connected to the buckle 109 attached to the side surface of the seat opposite to the fixing point of the seat belt end portion 107, so that the seat belt 104 is stretched from the shoulders of the occupant to the chest and the waist. Have been passed over.

In such a seat belt retractor, for example, it is necessary to momentarily pull in the seat belt.
For example, the combustion gas of explosive is used as power. That is, the combustion gas of the explosive powder instantaneously moves the piston in the cylinder, and the end portion of the seat belt is pulled in and locked by the movement of the cable whose one end is connected to the piston.

As a power generation device for retracting a seat belt of this type, for example, one disclosed in Japanese Patent Application Laid-Open No. 3-132447 is known. This will be described with reference to FIGS. FIG. 10 shows a seatbelt winding power generator, and FIG. 11 shows a gas generator of the seatbelt winding power generator.

In the figure, reference numeral 201 is a gas generator 2.
A housing for housing 02 is shown. A gas passage 203 for guiding the combustion gas generated in the gas generator 202 is formed in the housing 201. A cylinder 204 is provided on a side of the housing 201 so as to be substantially perpendicular to the axis of the housing 201.

That is, a male screw portion 205 is formed at the tip of the cylinder 204, and the male screw portion 205 is screwed into a female screw portion 206 formed in the housing 201 to connect the cylinder 204 to the housing 201. The opening of the cylinder 204 on the housing 201 side is communicated with the gas passage 203. This cylinder 2
A piston 207 is accommodated in the housing 04, and the cable 20 is provided on the housing 201 side of the piston 207.
8 is connected to one end.

The cable 208 passes through a part of the gas passage 203 and the cylinder 204 of the housing 201.
And is pulled out from the other side. Cable 208
A cable end portion 209 connected to an unillustrated emergency retracting device is fixed to the pull-out side end of the. The seal ring 21 is provided on the housing 201 side of the piston 207.
0 is arranged, and the cable seal 211 is arranged by fitting the cable 208.

A firing pin 213 is arranged laterally (above the drawing) of the stab primer 212 of the gas generator 202, and the stab probe 213 is pierced into the stab primer 212 by a predetermined firing pin actuator 214. It is possible. FIG. 11 shows the details of the gas generator 202.
Shows the casing.

One side 215A of the casing 215 is opened to form a detonator chamber 219, and the other side 215B is formed with a gas generating agent chamber 217 for accommodating an ignition agent and a driving agent 216. And, in front of the gas generating agent chamber 217,
A cover plate 218 is arranged, and the cover plate 218 is fixed to the casing 215 by caulking.

A stab bomb 212 is housed in the detonator chamber 219, and the stab 212 is fixed to the casing 215 by caulking. Further, a male screw portion 221 that is screwed into the female screw portion 220 of the housing 201 is formed on the outer periphery of the casing 215. The gas generating agent chamber 217 and the detonator chamber 219 are communicated with each other through the small diameter conduit 222.

[0014]

However, in the conventional seatbelt winding power generation device, the stab primer 21 is used.
The flame is smaller than the detonator chamber 219 at the time of the operation of
However, since the cross-sectional area of the small-diameter conduit 222 is much smaller than the cross-sectional area of the detonator chamber 219, the flame is less likely to concentrate and the heat supply may be restricted.

Therefore, the ignition of the igniting agent in the gas generating agent chamber 217 is lowered, the gas generation of the driving agent is delayed, and the time until the closing plate 218 of the gas generating chamber 217 is broken is delayed.
Therefore, the time required from the initial operation of the seat belt retractor to the retracting of the seat belt is delayed. The present invention has been made to solve the above-mentioned problems, and an object thereof is to allow a flame to be concentrated in a small-diameter pipe line during operation of a detonator and to quickly supply heat to a gas generant chamber. A gas generator of a power generation device for retracting a seat belt is provided.

[0016]

According to the first aspect of the present invention,
A cylindrical casing with one side opened, a cylindrical holder chamber formed on one side inside the casing, and a holder chamber that is continuous with the holder chamber through a step formed on the inner wall surface of the casing and inside the holder chamber. A gas generating agent chamber having a diameter smaller than the wall surface, an igniting agent and a driving agent accommodated in the gas generating agent chamber, and a detonator holder having a detonator chamber which is accommodated in the holder chamber and is open to one side of the casing, The caulking part formed on one side of the casing to press the detonator holder, the detonator held in the detonator chamber, the gas generator chamber formed in the detonator holder and the detonator chamber, and the taper angle at the detonator chamber side end And a small diameter conduit having an inverted conical taper portion of 60 ° to 120 °.

According to a second aspect of the present invention, in the first aspect, the maximum diameter portion of the inverse conical taper portion is 0.2 from the outer diameter of the detonator.
It is characterized by being smaller by 0.3 mm. According to a third aspect of the present invention, in the first or second aspect, a V groove is provided on the bottom surface of the gas generating agent chamber.

[0018]

According to the first aspect of the invention, when the firing pin collides with the surface of the detonator during a collision of an automobile, the detonator ignites,
The flame is guided to the small diameter pipe line while being concentrated at the inverted conical taper part, and the heat quantity supply to the gas generating agent chamber is promoted,
The igniting agent and the driving agent in the gas generating agent chamber explode to generate gas in the gas generating agent chamber.

Further, it is possible to prevent the combustion gas of the ignition agent and the driving agent from being jetted backward to the detonator side. In the invention according to claim 2, the detonator is held in the detonator chamber without falling into the inverted conical taper portion of the small diameter conduit.

According to the third aspect of the invention, the bottom surface of the gas generating agent chamber is broken by the internal pressure.

[0021]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 3 show a gas generator of a seatbelt winding power generation device according to an embodiment of the present invention. In FIG. 2, reference numeral 1 indicates a manifold case that houses the gas generator 2. The manifold case 1 has a stepped cylindrical portion 1B having a stepped portion 1A.
And a mounting portion 1C that is connected to the stepped cylindrical portion 1B and is inclined with respect to the axis of the stepped cylindrical portion 1B and integrally formed on the side of the stepped cylindrical portion 1B.

In the manifold case 1, a gas generator 2 is housed and a gas passage 3 for guiding the combustion gas generated in the gas generator 2 is formed. A cylinder 4 is projectingly provided at a mounting portion on the side of the manifold case 1. That is, a male screw portion 4A is formed at the tip of the cylinder 4, and the male screw portion 4A is formed in the mounting portion 1C of the manifold case 1 to form the female screw portion 1.
The cylinder 4 is connected to the manifold case 1 by being screwed into D, and the opening of the cylinder 4 on the manifold case 1 side is communicated with the gas passage 3.

A piston 5 is housed in the cylinder 4, and one end of a cable 6 is connected to the piston 5 on the side of the manifold case 1. The cable 6 passes through a part of the gas passage 3 and the manifold case 1
Is pulled out to the outside from the side opposite to the cylinder 4. 1 and 3 show the details of the gas generator 2, and reference numeral 7 in the drawings denotes a casing.

The casing 7 is made of aluminum having excellent corrosion resistance (for example, JIS: A5052), is formed in a cylindrical shape with a bottom, and a step portion 8 is formed on the inner wall surface. A large diameter portion 9 is formed on one side of the casing 7, and a cylindrical small diameter portion 10 that communicates with the large diameter portion 9 and is continuous via a step portion 8 is formed. A cylindrical holder chamber 12 is formed in the large diameter portion 9, a gas generating agent chamber 13 is formed continuously in the holder chamber 12 in the small diameter portion 10, and the gas generating agent chamber 13 is the gas generating agent chamber 1
It has a smaller diameter than the inner wall surface of 3.

The small-diameter portion 10 is closed by a bottom portion 11 having a V groove 11A integral therewith, and this bottom portion 11 is thin and has a V groove 11a.
The portion A is rupturable so that the gas generated when the ignition charge 20 and the driving charge 21, which will be described later, explode passes through and enters the gas passage 3. An opening 7A is formed in the large diameter portion 9 of the casing 7,
An annular crimping portion 14 is formed on the peripheral portion thereof.

A detonator holder 15 is housed in the holder chamber 12, and the detonator holder 15 is made of, for example, sulfur free-cutting steel (SUM).
And has a detonator chamber 16. The detonator chamber 16 is open toward one side of the casing 7. Detonator holder 15
The caulking portion 14 is caulked and fixed in the holder chamber 12. As shown in FIG. 3, before the caulking of the casing 7, the caulking portion 14 of the casing 7 is in a state shown by a chain double-dashed line, and the caulking portion 14 is inclined inwardly about 10 ° with respect to the axis of the casing 7. doing. Thereby, the caulking work can be facilitated. The caulking portion 14 is brought into a state shown by a solid line by pressing the caulking portion 14 shown by a two-dot chain line.

The detonator holder 15 is formed with a small-diameter conduit 17 which connects the gas generating agent chamber 13 and the detonator chamber 16.
A piercing detonator 18 is housed in the detonator chamber 16. Also,
An ignition agent 20 and a driving agent 21 are contained in the gas generating agent chamber 13. The ignition agent 20 is made of boron-based potassium nitrate. The driving agent 21 is composed of a single base propellant, and the single base propellant is composed of nitrocellulose, diphenylamine, potassium nitrate and graphite.

The above-mentioned small-diameter conduit 17 has a diameter of 0.5 to.
The length is 1.2 mm, and the total length is 5 to 8 times the diameter. As a result, it is possible to reliably prevent the reverse ejection of the combustion gas of the ignition charge 20 and the drive charge 21 toward the piercing primer 18 side. An inverted conical taper portion 17A having a taper angle of 60 ° to 120 ° is formed at the end of the small-diameter conduit 17 on the side of the detonator chamber 16.

Further, as shown in FIGS. 6 and 7, the diameter φA of the maximum diameter portion 17A 'of the inverted conical taper portion 17A is made smaller than the diameter D of the stab primer 18 by at least 0.2 to 0.3 mm. ing. Here, the inverted conical taper portion 17A of the small diameter conduit 17 will be described in detail. FIG. 4 shows an example in which the small diameter conduit 17 is tapered over the entire length.

In this case, the ignition agent 2 in the gas generating agent chamber 13
0, when the driving agent 21 burns, the small-diameter pipeline 17 is broken due to thermal shock on the lower surface, and the generated gas is back-injected, which hinders the retention of the internal pressure of the gas generating agent chamber 13. It may take too long to break the V-shaped groove 11A of the bottom portion 11. FIG. 5 shows an example in which a chamfer 17B of C1 or less is provided at the end portion of the small diameter conduit 17 on the detonator chamber 16 side.

With a chamfering degree of C1 or less, the flame of the piercing detonator 18 could not be concentrated and guided to the small diameter conduit 17, and there was no difference from the conventional small diameter conduit. 6 and 7
Shows the relationship between the stab primer 18 and the inverted conical taper portion 17A. When the stab primer 18 is held in the squib chamber 16, the stab surface 18A of the stab primer 18 may not ignite unless it is perpendicular to the firing pin piercing direction. Horizontal contact is required between the bottom surface 16A of the base and the bottom surface 18B of the stab primer 18. Therefore, the stab primer 18 to be used
Depending on the shape of the detonator chamber 16 and the shape of the
Since the taper angle of A is determined, the optimum range of taper angle must be set in order to suppress the reverse ejection and to provide the reverse conical taper portion which has the effect of concentrating the flame.

FIG. 8 shows the taper angle θ of the inverted conical taper portion 17A of the small diameter conduit 17 and the length L of the small diameter conduit in this embodiment.
Shows the relationship with. When the taper angle θ is less than 60 °,
The length L of the small-diameter pipe line 17 is shortened, the reverse ejection from the gas generating agent chamber 13 is generated, and the retention of the internal pressure is hindered.
It may take too long to break the V groove 11A.

On the other hand, when the taper angle θ exceeds 120 °, it approaches C1 chamfering, so that it becomes difficult for the flame to concentrate on the small diameter conduit 17. From the above results, the inverted conical taper portion 17
The taper angle θ of A must be in the range of 60 ° to 120 °. Further, the length L1 of the small diameter conduit 17 with the taper angle θ1 = 60 °, the length L2 of the small diameter conduit 17 with the taper angle θ2 = 90 °, and the small diameter conduit 17 with the taper angle θ3 = 120 °. The length L3 of each is 5 of the diameter of the small diameter conduit 17.
~ 8 times smaller. As a result, it is possible to reliably prevent the reverse ejection of the combustion gas of the ignition agent 20 and the driving agent 21 to the piercing primer 18 side.

The above-mentioned piercing detonator 18 is crimped inside the detonation chamber 16 by a pressing portion 19 formed on the peripheral edge of the opening of the detonation chamber 16. Further, the explosive powder contained in the stab primer 18 contains 0.5 to 10% by weight of tetracene.
Then, as shown in FIG. 3, the seal resin layer 22 is sandwiched between the detonator side surface 15A of the detonator holder 15 and the caulked portion 14 of the casing 7. Before the caulking of the caulking portion 14 of the casing 7, a sealing resin agent in a gel state, which is a base of the sealing resin layer 22, is applied to the detonator side surface 15A of the detonator holder 15 in advance. Then, for example, the seal resin layer 22 is formed by applying about 10 mg to 50 mg of a silicon-based resin and curing it before forming the caulked portion 14. The silicone-based resin has excellent viscoelasticity and forms a continuous coating film over a wide range even in the gel state at the time of application and the cured state at the time of curing, which ensures the sealing property.

The surface 15 of the detonator holder 15 opposite to the detonator side
The first thin film material 23 is sandwiched between B and the stepped portion 8 of the casing 7. The first thin film material 23 has a thickness of 50 μm.
It has a circular shape with a m of 20 to 20
It is formed by applying an adhesive having a thickness of 30 μm, and a polyester film or a polyimide film is used as the synthetic resin film.

As shown in FIG. 2, the gas generator 2 described above is used.
Is fixed in the manifold case 1 with a cap 24. A firing pin (not shown) is arranged on the side of the cap 24 (upper side in the drawing of FIG. 2).
It is possible to stab the stab primer 18 by a predetermined firing needle actuating device.

Next, the operation of this embodiment will be described. When a car collides, the firing pin actuating device is activated and the firing pin strikes
When piercing the surface of 8, the piercing primer 18 is ignited. The flame is guided to the small-diameter pipe line 17 while being concentrated at the inverted conical taper portion 17A of the small-diameter pipe line 17, and the gas generating agent chamber 1
The amount of heat supplied to the inside of the gas generating chamber 3 is promptly supplied, so that the ignition charge 20 in the gas generating agent chamber 13 is ignited and burned.

By this combustion, the V groove 11A in the bottom portion 11 of the casing 7 is ruptured, the combustion gas flows into the cylinder 4 through the gas passage 3, and the piston 5 in the cylinder 4 is moved. The cable 6 whose one end is connected to the piston 5 is moved, the emergency retractor is driven by the movement of the cable 6, and the seat belt is instantaneously retracted by the drive of the emergency retractor.

Since the detonator holder 15 is caulked by the caulking portion 14 of the casing 7, the sealing resin layer 22 is pressed by the caulking portion 14 onto the detonator side surface 15A of the detonator holder 15, and at the same time, the detonator holder The first thin film material 23 is pressed onto the step portion 8 by the surface 15B of the side 15 opposite to the detonator side. Further, the sealing resin layers 22 and 1 thin film material 23 are held in the large diameter portion 9 of the casing 7.

Therefore, the seal resin layer 22 and the first thin film material 23 prevent moisture from entering the gas generating agent chamber 13 from the outside, and the gas generating agent chamber 13 is kept in a hermetically sealed state from the outside. This prevents the igniting agent 20 and the driving agent 21 in the gas generating agent chamber 13 from getting wet due to the humidity. By the way, the pressure inside the gas generant chamber 13 is 10 ⁻³ atom / m 2.
It has become l.

According to the above-mentioned structure, the flame at the time of ignition of the stab primer 18 is connected to the bottom surface of the detonator chamber 16 in the small-diameter conduit 1.
The taper angle formed at the end of No. 7 is concentrated in the inverted conical taper portion 17A having a taper angle of 60 ° to 120 °, and heat supply to the gas generating agent chamber 13 can be promoted. In addition, piercing detonator 18
Even if the reverse conical taper portion 17A is provided on the bottom surface 16A of the detonation chamber 16, it can be held in a horizontal state with the bottom surface 16A of the detonation chamber 16 without falling into the reverse conical taper portion 17A.

Further, according to this embodiment, the sealing resin layer 22 and the first thin film material 23 prevent moisture from entering into the gas generating agent chamber 13 and seal the gas generating agent chamber 13. Can be kept in a state. Therefore, it is possible to prevent the moisture from the outside from moistening the igniting agent 20 and the driving agent 21 in the gas generating agent chamber 13, and it is possible to reliably ignite the igniting agent 20 and the driving agent 21.

Further, by utilizing the force of crimping the detonator holder 15 of the caulking portion 14 of the casing 7, the sealing resin layer 22 is closely adhered between the detonator side surface 15A of the detonator holder 15 and the caulking portion 14 of the casing 7. Yes, detonator holder 15
15B on the side opposite to the detonator side and the stepped portion 8 of the casing 7.
The first thin film material 23 can be adhered to the upper part of the gas generating agent chamber 13
It is not necessary to attach an O-ring that is normally used as a seal member to keep the seal in a sealed state.

Furthermore, when the caulking portion 14 of the casing 7 is caulked, the detonator side surface 15A of the detonator holder 15 is previously prepared.
Since the sealing resin agent in a gel state, which is the base of the sealing resin layer 22, is applied to the sealing resin layer 22, the sealing resin agent 22 fits into the shape of the caulking portion 14, and the sealing performance can be ensured. Since the first thin film material 23 is formed by applying a pressure sensitive adhesive to the synthetic resin film, the first thin film material 23 can be reliably positioned and the sealed state of the gas generating agent chamber 13 can be more reliably achieved. it can.

Further, even if moisture enters from between the manifold case 1 and the outer peripheral surface of the casing 7, the small-diameter portion 10 of the casing 7 is integrated with the bottom portion 11 thereof.
Since it is blocked by, it is possible to prevent moisture from entering the gas generating agent chamber 13. This is a conventional example (Figs. 10 and 1).
In 1), moisture that has entered between the female screw portion 220 of the housing 201 and the male screw portion 221 of the casing 215 flows from the casing 215 and the closing plate 218 to the gas generating agent chamber 2
Although there is a risk of infiltration into 17, the sealing effect is surely produced.

In this embodiment, a second thin film material made of a synthetic resin film that closes one end of the small diameter conduit 17 may be sandwiched between the bottom surface of the detonator chamber 16 and the piercing detonator 18. This prevents moisture from entering the gas generant chamber 13 from the detonator chamber 16 through the small-diameter conduit 17,
The certainty of ignition can be further increased. In this case, the second thin film material is formed by applying an adhesive to a synthetic resin film, so that the gas generating agent chamber 13 can be more reliably sealed.

In this embodiment, the first thin film material 23
Is formed by applying an adhesive to a synthetic resin film, but the first thin film material 23 can also be formed only by a synthetic resin film, and in this case also, the gas generating agent chamber 13 can be sealed. Further, in this embodiment, the first thin film material 2
In No. 3, the thickness is 50 μm and the thickness of the synthetic resin film is 20 to 30 μm, but it is not limited to such a numerical value.

In this embodiment, a polyester film or a polyimide film is used as the synthetic resin film, but the material is not limited to this. And again, in this embodiment,
Although a silicon-based resin is used as the seal resin layer, the material is not limited to such a material.

Further, in this embodiment, the case where the V groove 11A is provided in the bottom portion 11 of the gas generating agent chamber 13 has been described, but it may not be provided.

[0051]

As described above, according to the first aspect of the present invention, the flame due to the ignition of the detonator concentrates in the small-diameter conduit, promotes the supply of heat to the gas generating agent chamber, and The ignition agent and the driving agent can be promoted, the time required for breaking the bottom of the gas generating chamber can be shortened, and the time required for winding the seat belt can be shortened.

According to the invention described in claim 2, while having the effect of the invention described in claim 1, the detonator can be held horizontally with the bottom surface of the detonator chamber. According to the invention described in claim 3, while having the effects of claims 1 and 2, the bottom portion of the gas generating agent chamber can be reliably broken.

[Brief description of drawings]

FIG. 1 is a sectional view of essential parts of a gas generator of a seatbelt winding power generation device according to an embodiment of the present invention.

FIG. 2 is a sectional view of a seatbelt winding power generation device according to the embodiment.

FIG. 3 is an enlarged view showing a seal resin layer and a first thin film material of FIG.

FIG. 4 is a cross-sectional view of a detonator holder in which a tapered portion is provided up to a lower end of a small diameter conduit.

FIG. 5 is a cross-sectional view of a detonator holder in which an upper portion of a small diameter conduit is chamfered to C1 or less.

FIG. 6 is a plan view of a detonator holder showing a relationship between a stab primer and an inverted conical taper portion.

FIG. 7 is a sectional view of FIG. 6;

FIG. 8 is a sectional view of the detonator holder showing the relationship between the taper angle and the length of the small diameter conduit.

FIG. 9 is a perspective view showing a conventional seat bell mounted state.

FIG. 10 is a cross-sectional view of a conventional seat belt retracting power generation device.

FIG. 11 is a cross-sectional view of a gas generator of a conventional seatbelt winding power generation device.

[Explanation of symbols]

 2 Gas Generator 7 Casing 8 Step 11 Bottom 11A V Groove 12 Holder Chamber 13 Gas Generator Chamber 15 Detonator Holder 16 Detonator Chamber 17 Small Diameter Pipeline 17A Reverse Conical Tapered Section 18 Striking Detonator (Detonator) 20 Ignition Charge 21 Drive medicine

Claims (3)

[Claims] 1. A cylindrical casing having an opening on one side, a cylindrical holder chamber formed on one side of the casing, and a holder chamber continuous with a step portion formed on an inner wall surface of the casing. A gas generating agent chamber having a smaller diameter than the inner wall surface of the holder chamber, an igniting agent and a driving agent contained in the gas generating agent chamber, and a detonator chamber accommodated in the holder chamber and opening to one side of the casing. The detonator holder has, the caulking part formed on one side of the casing for pressing the detonator holder, the detonator held in the detonator chamber, and the gas generator chamber formed in the detonator holder and the detonator chamber and communicating with each other. The taper angle at the end is 60 ° to 12
A gas generator of a power generation device for retracting a seat belt, comprising: a small-diameter pipe line having a 0 ° inverted conical taper portion. 2. The gas generator for a seatbelt winding power generation device according to claim 1, wherein the maximum diameter portion of the inverted conical taper portion is smaller than the outer diameter of the detonator by 0.2 to 0.3 mm. 3. The gas generator for a seatbelt winding power generation device according to claim 1, wherein a V groove is provided on a bottom surface of the gas generating agent chamber.